Summary: I am updating to my previous post because Howard from TP-LINK suggested I update FW, but that's an invalid suggestion. The modem I bought is revision 5.1. Both router FW and DSL data pump FW are newer than the latest posted on TP-LINK website Howard provided. Various HW versions of this unit, 4.0, 4.1, 5.0, 5.1 all uses some combination of TrendChip + Ralink devices. I went exchanged my rev5.1 for an rev5.0 modem and had the exact issue.
Pros: Solid DSL modem function that is powered by TrendChip DSL chips.
Cons: Super unstable wireless N router that is powered by buggy Ralink Wifi Chips.
Summary: A solid DSL modem but horrible WiFi router. Ralink WiFi killed the attractiveness of the TrendChip DSL modem, making this all-in-one unit a pain in the rear to use. If you think your AT&T provided 2Wire is unreliable, this thing is 10x more unreliable.
Pros: DSL modem part is powered by TrendChip aquired by Ralink. The setup is very easy as it had drop down menu support for every single DSL ISP in the US I can think of. The connection speed is high and stable and virtually no CRC errors. A lot of flexibility such as changing MTU and MSS to optimize the DSL connection.
Cons: Ralink powered 802.11n 150N - PURE JUNK. -Very low signal penetration even on "high" setting. -Insanely high transmit error count according to the Log. -Authentication function has serious bugs. After a mere 24 hours of running, it refused to let my laptops, phones regain WiFi access to the router. While set top box that was left on overnight was able to maintain WiFi connection established the night before. I had to power cycle the router almost every 24 hours to res...
Excerpt: Please stay away from this modem if you're buying it for wi-fi connectivity. For the first week wi-fi was working properly, but later whenever i turn on the wifi and connect it with a mobile, the modem restarts automatically and i never able to connect with a mobile in wifi. google for this restart problem in this modem and you will not buy it for sure. No problem with LAN connectivity though.